Sealant for polyethylene fuel tank?

[Rob Turk]

I'm looking for a sealant or kit to seal brass NPT inserts into a
polyethylene tank. This is a Kitfox header tank that has developed a leak at
one of the inserts. I'm probably going to use Mogas that has ethanol
additives. Any hints, tips, thoughts?

Thanks,
Rob

[[email protected]]

On Mar 1, 12:55 am, "Rob Turk" > wrote:
> I'm looking for a sealant or kit to seal brass NPT inserts into a
> polyethylene tank. This is a Kitfox header tank that has developed a leak at
> one of the inserts. I'm probably going to use Mogas that has ethanol
> additives. Any hints, tips, thoughts?
>
> Thanks,
> Rob

ProSeal ....... or the generic =?

Take it to an RV shop and have the insert "welded" in?

[Dennis Fetters]

wrote:
> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>
>>I'm looking for a sealant or kit to seal brass NPT inserts into a
>>polyethylene tank. This is a Kitfox header tank that has developed a leak at
>>one of the inserts. I'm probably going to use Mogas that has ethanol
>>additives. Any hints, tips, thoughts?
>>
>>Thanks,
>>Rob

Red high temperature silicon sealer. Local hardware store. Clean the
threads with alcohol and apply sealer. Lasts forever.

[Charlie[_2_]]

Dennis Fetters wrote:
> wrote:
>> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>>
>>> I'm looking for a sealant or kit to seal brass NPT inserts into a
>>> polyethylene tank. This is a Kitfox header tank that has developed a
>>> leak at
>>> one of the inserts. I'm probably going to use Mogas that has ethanol
>>> additives. Any hints, tips, thoughts?
>>>
>>> Thanks,
>>> Rob
>
> Red high temperature silicon sealer. Local hardware store. Clean the
> threads with alcohol and apply sealer. Lasts forever.
I'd check the label first. Last time I looked, it specifically excluded
use near gasoline.

The kinds I've seen will swell up & shed chunks into the fuel system.

Charlie

[clare at snyder.on.ca]

On Thu, 01 Mar 2007 20:37:38 GMT, Dennis Fetters
> wrote:

wrote:
>> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>>
>>>I'm looking for a sealant or kit to seal brass NPT inserts into a
>>>polyethylene tank. This is a Kitfox header tank that has developed a leak at
>>>one of the inserts. I'm probably going to use Mogas that has ethanol
>>>additives. Any hints, tips, thoughts?
>>>
>>>Thanks,
>>>Rob
>
>Red high temperature silicon sealer. Local hardware store. Clean the
>threads with alcohol and apply sealer. Lasts forever.


Except RTV is NOT gasoline resistant.

--
Posted via a free Usenet account from http://www.teranews.com

[Morgans[_2_]]

<clare at snyder.on.ca> wrote
>
> Except RTV is NOT gasoline resistant.

Right.

How about some welding with a pencil torch, and some cut up strips of like
plastic?

The key is to keep the fitting hot enough so the strips of plastic stay
melted onto it, and cools and hardens after the heat is taken away, and
enough heat is also applied to the tank plastic and the strips so that they
toughly melt together.

It is a fine line, getting the tank hot enough to soften, but not melt
through.

The other option that comes to mind is a fitting that is a plate with
threads in it for the fuel line fitting, installed inside the tank and
another plate on the outside the tank, with a gasket on both sides, and
screws holding them all together. That could be done second, if the dreaded
melt-through happened around the fitting. This could be manufactured at
home, if one was a bit handy, and creative.
--
Jim in NC

[cavelamb himself]

wrote:
> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>
>>I'm looking for a sealant or kit to seal brass NPT inserts into a
>>polyethylene tank. This is a Kitfox header tank that has developed a leak at
>>one of the inserts. I'm probably going to use Mogas that has ethanol
>>additives. Any hints, tips, thoughts?
>>
>>Thanks,
>>Rob

Polyethylene is pretty hard to glue anything to.


LEAF has several sizes of rubber "plugs" that a barbed brass fitting
can fit into. Drill a hole, press in the rubber plug, and poke the
fitting into that.

IIRC, I used 1/4" on my plane, but I think they have a 3/8" also.

Other than that?

New Tank?

Richard

[Earl]

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan

On Thu, 1 Mar 2007 22:30:32 -0500, "Morgans"
> wrote:

>
><clare at snyder.on.ca> wrote
>>
>> Except RTV is NOT gasoline resistant.
>
>Right.
>
>How about some welding with a pencil torch, and some cut up strips of like
>plastic?
>
>The key is to keep the fitting hot enough so the strips of plastic stay
>melted onto it, and cools and hardens after the heat is taken away, and
>enough heat is also applied to the tank plastic and the strips so that they
>toughly melt together.
>
>It is a fine line, getting the tank hot enough to soften, but not melt
>through.
>
>The other option that comes to mind is a fitting that is a plate with
>threads in it for the fuel line fitting, installed inside the tank and
>another plate on the outside the tank, with a gasket on both sides, and
>screws holding them all together. That could be done second, if the dreaded
>melt-through happened around the fitting. This could be manufactured at
>home, if one was a bit handy, and creative.

[Rob Turk]

"Earl" > wrote in message
...
> Rob said his tank had developed a leak. That would mean that there had
> been gasoline in the tank. I don't think anyone would suggest welding
> a used metal tank, how could it be any safer with a plasic one?
>
>
> Steve in Michigan

You got it ;-) I like flying, but not *that* kind flight...

Rob

[Dennis Fetters]

Charlie wrote:
> Dennis Fetters wrote:
>
>> wrote:
>>
>>> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>>>
>>>> I'm looking for a sealant or kit to seal brass NPT inserts into a
>>>> polyethylene tank. This is a Kitfox header tank that has developed a
>>>> leak at
>>>> one of the inserts. I'm probably going to use Mogas that has ethanol
>>>> additives. Any hints, tips, thoughts?
>>>>
>>>> Thanks,
>>>> Rob
>>
>>
>> Red high temperature silicon sealer. Local hardware store. Clean the
>> threads with alcohol and apply sealer. Lasts forever.
>
> I'd check the label first. Last time I looked, it specifically excluded
> use near gasoline.
>
> The kinds I've seen will swell up & shed chunks into the fuel system.
>
> Charlie


Correct Charlie. But you never use any sealant in an amount that will
transfer product into the tank.

Problem: The fellow has a polyethylene tank, which nothing likes to
stick to anyway. Add to that, it has fuel and maybe even oil in the
tank, making it worse. Can't use a sealant that hardens, it will crack
and leak.

Solution: Use RTV in a small amount on only the threads of the insert
after cleaning both the male and female parts. Install the insert so
none of the RTV goes into the tank. Allow the gas to swell the RTV
inside the threads, which helps the seal.

Right, it has drawbacks if not used correctly, but it is the only good
solution for the situation. The only other solution would be to ream the
hole out and replace the threaded insert with a Dapco rubber bushing and
insert, better anyway. You can find them at Aircraft Spruce.

Hope this helps.

[Morgans[_2_]]

"Earl" > wrote

> Rob said his tank had developed a leak. That would mean that there had
> been gasoline in the tank. I don't think anyone would suggest welding
> a used metal tank, how could it be any safer with a plastic one?

Doh! I realized that, right after I hit send. I'm sure I would not have
done that if it were sitting there in front of me!

A soldering iron would be safe, and almost as effective at doing a little
plastic welding. It is kinda' fun, if you have ever done it before.
--
Jim in NC

[[email protected]]

On Mar 2, 12:18 pm, "Morgans" > wrote:
> "Earl" > wrote
>
> > Rob said his tank had developed a leak. That would mean that there had
> > been gasoline in the tank. I don't think anyone would suggest welding
> > a used metal tank, how could it be any safer with a plastic one?
>
> Doh! I realized that, right after I hit send. I'm sure I would not have
> done that if it were sitting there in front of me!

When I said "welded" in my original reply I had.assumed thatmost would
take that as the "normal" method of welding plastic - with a plastic
welder that uses hot air.

Assumptions generaly BITE!

As for the idea of red silisone - don't. Been there done that. Gave
up the practice many years ago. No matter how small an amount you use
the gas wil eventually swell it up and leak through. A waste of time
and materials - IMHO

[Orval Fairbairn]

In article >,
Earl > wrote:

> Rob said his tank had developed a leak. That would mean that there had
> been gasoline in the tank. I don't think anyone would suggest welding
> a used metal tank, how could it be any safer with a plasic one?
>
>
> Steve in Michigan

Actually, it is quite safe -- if done right. I have done this several
times.

1. Look up "Dry Ice" in your Yellow Pages.

2. Get the smallest amount they will sell you (usually about 5 lb.)

3. Put it in the tank and let sit for about 1/2 hour.

The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
from the tank and will not support combustion.

The nice thing about dry ice is that it leaves no residue, unlike
filling the tank with water

[clare at snyder.on.ca]

On Fri, 02 Mar 2007 20:51:21 GMT, Orval Fairbairn
> wrote:

>In article >,
> Earl > wrote:
>
>> Rob said his tank had developed a leak. That would mean that there had
>> been gasoline in the tank. I don't think anyone would suggest welding
>> a used metal tank, how could it be any safer with a plasic one?
>>
>>
>> Steve in Michigan
>
>Actually, it is quite safe -- if done right. I have done this several
>times.
>
>1. Look up "Dry Ice" in your Yellow Pages.
>
>2. Get the smallest amount they will sell you (usually about 5 lb.)
>
>3. Put it in the tank and let sit for about 1/2 hour.
>
>The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
>from the tank and will not support combustion.
>
>The nice thing about dry ice is that it leaves no residue, unlike
>filling the tank with water

Welded (brazed) a patch on the oilpan of a '64 Riviera one day without
pulling it. Rinsed out all the oil I could, first with varsol, then
hot water - and filled the crankcase with a CO2 extinguisher. Had the
apprentice sitting on the fender, giving it a little shot every minute
or so untill I has the patch fully sweated on. (guy had driven into
the rebar used to spike a parking cub down and HAD to leave for
Chicago that evening - from Kitchener Ontario)

--
Posted via a free Usenet account from http://www.teranews.com

[Cy Galley]

They make sealed end pop rivets. Use them to sandwich some pro-seal between
the tank and an aluminum plate. Tap the plate for the fitting.

The old time fix is to rub the leak with a bar of soap. Seals the leak and
gas won't dissolve it.


"cavelamb himself" > wrote in message
nk.net...
> wrote:
>> On Mar 1, 12:55 am, "Rob Turk" > wrote:
>>
>>>I'm looking for a sealant or kit to seal brass NPT inserts into a
>>>polyethylene tank. This is a Kitfox header tank that has developed a leak
>>>at
>>>one of the inserts. I'm probably going to use Mogas that has ethanol
>>>additives. Any hints, tips, thoughts?
>>>
>>>Thanks,
>>>Rob
>
> Polyethylene is pretty hard to glue anything to.
>
>
> LEAF has several sizes of rubber "plugs" that a barbed brass fitting
> can fit into. Drill a hole, press in the rubber plug, and poke the
> fitting into that.
>
> IIRC, I used 1/4" on my plane, but I think they have a 3/8" also.
>
> Other than that?
>
> New Tank?
>
> Richard

[cavelamb himself]

Orval Fairbairn wrote:

> In article >,
> Earl > wrote:
>
>
>>Rob said his tank had developed a leak. That would mean that there had
>>been gasoline in the tank. I don't think anyone would suggest welding
>>a used metal tank, how could it be any safer with a plasic one?
>>
>>
>>Steve in Michigan
>
>
> Actually, it is quite safe -- if done right. I have done this several
> times.
>
> 1. Look up "Dry Ice" in your Yellow Pages.
>
> 2. Get the smallest amount they will sell you (usually about 5 lb.)
>
> 3. Put it in the tank and let sit for about 1/2 hour.
>
> The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
> from the tank and will not support combustion.
>
> The nice thing about dry ice is that it leaves no residue, unlike
> filling the tank with water

I've been using dry ice for a while now to extend the ice box on my
boat. One summer and the cooler is crazed, cracked, and nearly useless.

Wouldn't recommend this aproach on a plastic fuel tank.


I'm gonna stick with this one:
http://store.leadingedgeairfoils.com/index.php?cPath=548_436_568

Fuel Tank Bushing
SKU: H7285
$1.00

Richard

[Rob Turk]

"TerryJ" <suptjudatcomcastdotnet> wrote in message
. ..
> Teflon tape from ACE hardware....
>
> "Rob Turk" > wrote in message
> . ..
>> I'm looking for a sealant or kit to seal brass NPT inserts into a
>> polyethylene tank. This is a Kitfox header tank that has developed a leak
>> at one of the inserts. I'm probably going to use Mogas that has ethanol
>> additives. Any hints, tips, thoughts?
>>
>> Thanks,
>> Rob

Tried that, but it appears to be eaten by the ethanol additives from Mogas.

Rob

[Rob Turk]

"cavelamb himself" > wrote in message
nk.net...
>
>
> I'm gonna stick with this one:
> http://store.leadingedgeairfoils.com/index.php?cPath=548_436_568
>
> Fuel Tank Bushing
> SKU: H7285
> $1.00
>
> Richard

That looks pretty convincing. Someone else suggested Dapco, which has the
same plugs. I e-mailed Dapco and they confirmed their product to be good for
this, including being Ethanol resilient. They are an OEM supplier so I don't
think they will do small quantities, but I have not asked yet.

Rob

[[email protected]]

On Mar 3, 2:32 am, "Rob Turk" > wrote:
> "TerryJ" <suptjudatcomcastdotnet> wrote in message
>
> . ..
>
> > Teflon tape from ACE hardware....
>
> > "Rob Turk" > wrote in message
> . ..
> >> I'm looking for a sealant or kit to seal brass NPT inserts into a
> >> polyethylene tank. This is aKitfoxheader tank that has developed a leak
> >> at one of the inserts. I'm probably going to use Mogas that has ethanol
> >> additives. Any hints, tips, thoughts?
>
> >> Thanks,
> >> Rob
>
> Tried that, but it appears to be eaten by the ethanol additives from Mogas.
>
> Rob

There is only one thing that will work that I have tried other than
plastic welding.
Get a stick of the 2 part epoxy for fuel tanks.
Knead together, and wrap around the thread then screw in the fitting.
Once in make sure you always hold a wrench on it when you are screwing
other fittings into it or it might break the seal.

Mine has not leaked in over 3 years now.

More Kitfox info and movies and GPS plotting stuff here http://www.cfisher.com


Dave

[clare at snyder.on.ca]

On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
> wrote:

>"cavelamb himself" > wrote in message
nk.net...
>>
>>
>> I'm gonna stick with this one:
>> http://store.leadingedgeairfoils.com/index.php?cPath=548_436_568
>>
>> Fuel Tank Bushing
>> SKU: H7285
>> $1.00
>>
>> Richard
>
>That looks pretty convincing. Someone else suggested Dapco, which has the
>same plugs. I e-mailed Dapco and they confirmed their product to be good for
>this, including being Ethanol resilient. They are an OEM supplier so I don't
>think they will do small quantities, but I have not asked yet.
>
>Rob
>
Can you hog it out to the next size pipe thread and put a reducer
bushing in? Make sure you use a tapered pipe thread and do not
overtighten it. Make sure you use FLEXIBLE line from the tank to the
fuselage. Rigid tubing WILL eventually take the threts out of the poly
tank.

--
Posted via a free Usenet account from http://www.teranews.com

[clare at snyder.on.ca]

On Sat, 3 Mar 2007 08:32:15 +0100, "Rob Turk"
> wrote:

>"TerryJ" <suptjudatcomcastdotnet> wrote in message
. ..
>> Teflon tape from ACE hardware....
>>
>> "Rob Turk" > wrote in message
>> . ..
>>> I'm looking for a sealant or kit to seal brass NPT inserts into a
>>> polyethylene tank. This is a Kitfox header tank that has developed a leak
>>> at one of the inserts. I'm probably going to use Mogas that has ethanol
>>> additives. Any hints, tips, thoughts?
>>>
>>> Thanks,
>>> Rob
>
>Tried that, but it appears to be eaten by the ethanol additives from Mogas.
>
>Rob
>
Ethanol will NOT disolve teflon. It is the material of choice for
handling ethanol fuels.

--
Posted via a free Usenet account from http://www.teranews.com

[Drew Dalgleish]

On Sat, 03 Mar 2007 16:21:48 -0500, clare at snyder.on.ca wrote:

>On Sat, 3 Mar 2007 08:32:15 +0100, "Rob Turk"
> wrote:
>
>>"TerryJ" <suptjudatcomcastdotnet> wrote in message
. ..
>>> Teflon tape from ACE hardware....
>>>
>>> "Rob Turk" > wrote in message
>>> . ..
>>>> I'm looking for a sealant or kit to seal brass NPT inserts into a
>>>> polyethylene tank. This is a Kitfox header tank that has developed a leak
>>>> at one of the inserts. I'm probably going to use Mogas that has ethanol
>>>> additives. Any hints, tips, thoughts?
>>>>
>>>> Thanks,
>>>> Rob
>>
>>Tried that, but it appears to be eaten by the ethanol additives from Mogas.
>>
>>Rob
>>
>Ethanol will NOT disolve teflon. It is the material of choice for
>handling ethanol fuels.
>
>--
>Posted via a free Usenet account from http://www.teranews.com
>
I like locktite 592 thread sealant for jobs like this. It's a teflon
based pipe dope that doesn't dry out.

[Rob Turk]

<clare at snyder.on.ca> wrote in message
...
> On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
> Can you hog it out to the next size pipe thread and put a reducer
> bushing in? Make sure you use a tapered pipe thread and do not
> overtighten it. Make sure you use FLEXIBLE line from the tank to the
> fuselage. Rigid tubing WILL eventually take the threts out of the poly
> tank.
>

That would get me back to the starting situation; What do I use to seal the
bushing, considering nothing seems to stick to polyethylene..

Rob

[GeorgeB]

On Sat, 3 Mar 2007 22:53:58 +0100, "Rob Turk"
> wrote:

><clare at snyder.on.ca> wrote in message
...
>> On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
>> Can you hog it out to the next size pipe thread and put a reducer
>> bushing in? Make sure you use a tapered pipe thread and do not
>> overtighten it. Make sure you use FLEXIBLE line from the tank to the
>> fuselage. Rigid tubing WILL eventually take the threts out of the poly
>> tank.
>>
>
>That would get me back to the starting situation; What do I use to seal the
>bushing, considering nothing seems to stick to polyethylene..
>
>Rob

Buna or "Viton" o-rings as are used on o-ring fittings, face seal
fittings, and flanges the world over. Compress, don't twist. I don't
have a link to the AN series, but SAE (J1926) or BSPP (ISO 1179) work
well with light hydrocarbons and alcohols. My specific experience is
in hydraulics where they are used from vacuum to about 600 bar (9000
psi)

I'm making one REAL BIG ASS U ME thing ... that you can get into the
tank to install a nut. IF not, the expansion plugs mentioned earlier
are a good option.

Note that these fittings are usually steel in my industry, but the AN
versions are also in aluminum; you'll pay more, save weight, but get
the same ports.

Aside; whoever said teflon tape is attacked by gasoline ... I'd like
more information; I've used it many times with no problems of that
sort. My objection with it in a fuel system is that the installation
will leave small particles that plug orifices ... like carburetor
jets.

[d.l.anderson]

On Sat, 3 Mar 2007 22:53:58 +0100, "Rob Turk"
> wrote:

><clare at snyder.on.ca> wrote in message
...
>> On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
>> Can you hog it out to the next size pipe thread and put a reducer
>> bushing in? Make sure you use a tapered pipe thread and do not
>> overtighten it. Make sure you use FLEXIBLE line from the tank to the
>> fuselage. Rigid tubing WILL eventually take the threts out of the poly
>> tank.
>>
>
>That would get me back to the starting situation; What do I use to seal the
>bushing, considering nothing seems to stick to polyethylene..
>
>Rob
>

There is a marine product for repairing polyethylene: PolyDura
http://www.marinetex.com/PRODUCT%20PAGE_files/All%20PolyDura%20Info/Poly%20Dura%20FAQ%20page.htm

However, the tank must be flame treated for it to adhere!

"Can I use PolyDura to fix my polyethylene gas tank?

We do not recommend flame-treating any project that may be associated
with flammable materials. Flame-treating of items such as fuel tanks,
chemical tanks, pipelines or other flammable containers is not
recommended due to the danger of explosion or fire."

For sealing to polyethylene, Dow 730 fluorosilicone rubber:
http://www.aircraftspruce.com/catalog/appages/dow730.php
http://www.skygeek.com/rtv730-3oz.html

Pretty expensive! Dow 730 is specified in the maintenance manual for
the DeHavilland DHC-8, for tacking down rubber seals in the wing fuel
cell access panels. However, the Dow 730 Product Data Sheet
http://www.dowcorning.com/applications/search/default.aspx?R=406EN
states the following limitations:

• On Teflon®1-coated materials,
polyethylene, polypropylene or
methylmethacrylate (Plexiglas®2);
sealant will not adhere well
• On or near sensitive metals such as
copper, brass, zinc, carbon steel,
galvanized iron or magnesium; these
metals may be corroded, especially
in confined cure conditions, due to
the acetic acid released during the
cure


Or, you could try a visit to your friendly ski repair shop and pick
their brains about hot-air welding of polyethylene ski bases.
http://www.svst.com/page5.html

Harbor Freight offers a hot-air plastic welder, $29.95 :
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41592

This sounds like a Proseal-type compound:
http://www.patentstorm.us/patents/6113820-claims.html
Although they package 2 part polysulfide rubber compounds in
polyethylene containers, from my experience it sticks to some of them
pretty well.

Post some feedback on your results, please.

D. Anderson

[clare at snyder.on.ca]

On Sat, 3 Mar 2007 22:53:58 +0100, "Rob Turk"
> wrote:

><clare at snyder.on.ca> wrote in message
...
>> On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
>> Can you hog it out to the next size pipe thread and put a reducer
>> bushing in? Make sure you use a tapered pipe thread and do not
>> overtighten it. Make sure you use FLEXIBLE line from the tank to the
>> fuselage. Rigid tubing WILL eventually take the threts out of the poly
>> tank.
>>
>
>That would get me back to the starting situation; What do I use to seal the
>bushing, considering nothing seems to stick to polyethylene..
>
>Rob
>
ABSOLUTELY NOTHING. A tapered pipe thread is a "dry seal" thread,
particularly into Poly.


--
Posted via a free Usenet account from http://www.teranews.com

[Morgans[_2_]]

"Rob Turk" > wrote

> That would get me back to the starting situation; What do I use to seal
> the bushing, considering nothing seems to stick to polyethylene..

I think part of the problem here, is that everyone does not know exactly
what you are working with, such as:

Is the location of the fitting in the tank built up at all, or is it like
someone just punched a hole in the tank in a random location, and stuck the
fitting in?

Can you give us a part number, or picture on a site, or at least a
description of the type of fitting that is penetrating the tank that you are
presently using, that is not working?
--
Jim in NC

[Rob Turk]

"Morgans" > wrote in message
...
>
> "Rob Turk" > wrote
>
>> That would get me back to the starting situation; What do I use to seal
>> the bushing, considering nothing seems to stick to polyethylene..
>
> I think part of the problem here, is that everyone does not know exactly
> what you are working with, such as:
>
> Is the location of the fitting in the tank built up at all, or is it like
> someone just punched a hole in the tank in a random location, and stuck
> the fitting in?
>
> Can you give us a part number, or picture on a site, or at least a
> description of the type of fitting that is penetrating the tank that you
> are presently using, that is not working?
> --
> Jim in NC
>

Here's a link to a Kitfox builders site. It's not my site, but it has good
pictures of the exact same header tank itself:
http://www.scoobysworkshop.com/2005pix/headerConnectors_small.jpg
http://www.scoobysworkshop.com/2005pix/headerTankDone_small.jpg

There's no real build up, but the tank has thick enough walls to allow a bit
of thread. There's no openings to allow nuts to go in, meaning that viton
ring approach is practically rules out. The guy that made the pictures has
used some kind of kit or glue to bond the brass inserts into the tank, and
it's this kit that eventually gives way and develops leaks. We got the tank
from a previous owner who was honest enough to tell us about the problem
beforehand and we're trying to solve this in a reliable way.

Rob


Rob

[d.l.anderson]

>Here's a link to a Kitfox builders site. It's not my site, but it has good
>pictures of the exact same header tank itself:
>http://www.scoobysworkshop.com/2005pix/headerConnectors_small.jpg
>http://www.scoobysworkshop.com/2005pix/headerTankDone_small.jpg
>
>There's no real build up, but the tank has thick enough walls to allow a bit
>of thread. There's no openings to allow nuts to go in, meaning that viton
>ring approach is practically rules out. The guy that made the pictures has
>used some kind of kit or glue to bond the brass inserts into the tank, and
>it's this kit that eventually gives way and develops leaks. We got the tank
>from a previous owner who was honest enough to tell us about the problem
>beforehand and we're trying to solve this in a reliable way.
>
>Rob
>
>
>Rob
>


OK, bigger pictures at:
http://www.scoobysworkshop.com/2005pix/headerConnectors.jpg
http://www.scoobysworkshop.com/2005pix/headerTankDone.jpg

Hmmm, looks like no bosses...just threaded into the tank with a sealer
and cinched up with a nut. Is there also a pickup screen on the
inside of the tank, connected to the AN angle fitting? How about a
low point quick drain? Might be a good idea.

You could use a hole saw to cut an access hole that could later be
closed using an expanding, fuel resistant "Thermos style" pressure
cap. Four different sizes at Wicks Aircraft. The 2" TURN-TITE FUEL
CAP looks to be the most secure.
http://www.wicksaircraft.com/catalog/product_cat.php/subid=301/index.html
Then you could fish a straight AN bulkhead fitting like this:
http://www.wicksaircraft.com/catalog/product_detail.php/pid=3708~subid=955/index.html
with an O-ring on it down a wire and pull it out far enough to get a
bulkhead nut on it.

You should provide some means of inspecting or cleaning out the inside
of the tank anyway.

D.Anderson

[Blueskies]

"Rob Turk" > wrote in message . ..
: <clare at snyder.on.ca> wrote in message
: ...
: > On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
: > Can you hog it out to the next size pipe thread and put a reducer
: > bushing in? Make sure you use a tapered pipe thread and do not
: > overtighten it. Make sure you use FLEXIBLE line from the tank to the
: > fuselage. Rigid tubing WILL eventually take the threts out of the poly
: > tank.
: >
:
: That would get me back to the starting situation; What do I use to seal the
: bushing, considering nothing seems to stick to polyethylene..
:
: Rob
:
:

The polyurethane itself should act as a sealer. It will cold flow around the threads. You need to be sure all the
threads are smooth to some degree and not over tighten...

[Rob Turk]

"d.l.anderson" > wrote in message
...
>
>>Here's a link to a Kitfox builders site. It's not my site, but it has good
>>pictures of the exact same header tank itself:
>>http://www.scoobysworkshop.com/2005pix/headerConnectors_small.jpg
>>http://www.scoobysworkshop.com/2005pix/headerTankDone_small.jpg
>>
>>There's no real build up, but the tank has thick enough walls to allow a
>>bit
>>of thread. There's no openings to allow nuts to go in, meaning that viton
>>ring approach is practically rules out. The guy that made the pictures has
>>used some kind of kit or glue to bond the brass inserts into the tank, and
>>it's this kit that eventually gives way and develops leaks. We got the
>>tank
>>from a previous owner who was honest enough to tell us about the problem
>>beforehand and we're trying to solve this in a reliable way.
>>
>>Rob
>
>
> OK, bigger pictures at:
> http://www.scoobysworkshop.com/2005pix/headerConnectors.jpg
> http://www.scoobysworkshop.com/2005pix/headerTankDone.jpg
>
> Hmmm, looks like no bosses...just threaded into the tank with a sealer
> and cinched up with a nut. Is there also a pickup screen on the
> inside of the tank, connected to the AN angle fitting? How about a
> low point quick drain? Might be a good idea.
>
> You could use a hole saw to cut an access hole that could later be
> closed using an expanding, fuel resistant "Thermos style" pressure
> cap. Four different sizes at Wicks Aircraft. The 2" TURN-TITE FUEL
> CAP looks to be the most secure.
> http://www.wicksaircraft.com/catalog/product_cat.php/subid=301/index.html
> Then you could fish a straight AN bulkhead fitting like this:
> http://www.wicksaircraft.com/catalog/product_detail.php/pid=3708~subid=955/index.html
> with an O-ring on it down a wire and pull it out far enough to get a
> bulkhead nut on it.
>
> You should provide some means of inspecting or cleaning out the inside
> of the tank anyway.
>
> D.Anderson

Good advice, thanks everyone!

The tank already has a low point drain connection which attached to a drain
valve. Construction is the same brass insert. There's no pickup screen on
the AN fitting, it's again the same brass insert with a standard AN
connection screwed in.

As you can (barely) tell from the picture, there's also two connections on
the righthand side. The top one is unused. The bottom one fits a 'low fuel'
level detector. Plenty of holes, but none large enough to do much fishing.
Anyway, I have plenty of options to explore from this thread, thanks again
everyone.

Rob

[Morgans[_2_]]

"d.l.anderson" wrote
>
> Hmmm, looks like no bosses...just threaded into the tank with a sealer
> and cinched up with a nut. Is there also a pickup screen on the
> inside of the tank, connected to the AN angle fitting? How about a
> low point quick drain? Might be a good idea.
>
> You could use a hole saw to cut an access hole that could later be
> closed using an expanding, fuel resistant "Thermos style" pressure
> cap. Four different sizes at Wicks Aircraft. The 2" TURN-TITE FUEL
> CAP looks to be the most secure.
> http://www.wicksaircraft.com/catalog/product_cat.php/subid=301/index.html
> Then you could fish a straight AN bulkhead fitting like this:
> http://www.wicksaircraft.com/catalog/product_detail.php/pid=3708~subid=955/index.html
> with an O-ring on it down a wire and pull it out far enough to get a
> bulkhead nut on it.
>
> You should provide some means of inspecting or cleaning out the inside
> of the tank anyway.


I agree with everything in this post. No drain, no inspection plate or cap?
Not my ideal setup, I think.

Also, depending on sealants on threads (in the thin walls of a tank) to keep
fuel from leaking into the cockpit....Gives me the "willies."

Get a way to put compression fittings inside the tank, or install a boss
with plastic welding, or something.

A fire in a cockpit would be one of the most terrible ways to die that I
could think of.
--
Jim in NC

[Capt. Geoffrey Thorpe]

"d.l.anderson" > wrote in message
...
>
<...>
> You could use a hole saw to cut an access hole that could later be
> closed using an expanding, fuel resistant "Thermos style" pressure
> cap. Four different sizes at Wicks Aircraft. The 2" TURN-TITE FUEL
> CAP looks to be the most secure.
> http://www.wicksaircraft.com/catalog/product_cat.php/subid=301/index.html

I watched two people burn to death in front of the airshow crowd at Oshkosh
20 some years ago when this type of fuel cap popped off after a T-18 hit the
ground inverted. The occupants survived the impact and were pleading for
help on the radio. Unfortunatly, the aircraft was sitting in a big puddle of
burning fuel and no one could get to them. By the time the fire trucks
arrived, they were dead.

This style of fuel cap falls into my "not recommended" catagory.

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Morgans[_2_]]

"Capt. Geoffrey Thorpe" > wrote
>
> I watched two people burn to death in front of the airshow crowd at
> Oshkosh 20 some years ago when this type of fuel cap popped off after a
> T-18 hit the ground inverted. The occupants survived the impact and were
> pleading for help on the radio. Unfortunatly, the aircraft was sitting in
> a big puddle of burning fuel and no one could get to them. By the time the
> fire trucks arrived, they were dead.
>
> This style of fuel cap falls into my "not recommended" catagory.

Wow, rough way to go. I would have to agree with you.

I would think that a fitting threaded into less than 1/8" of plastic would
fall into the same type of danger category. They could blow out, or be
pushed out, with a minimum of effort, not to mention the current problem of
leakage.

An inspection and access hole could be made so easily, and a plate of
aluminum and gasket with a backing plate (or ring) to screw into could be
done so easily, I would think that would be the first choice. Then, a
fitting with a true nut and O-ring could be used on all of the fittings,
with security, and no problems with leaks.

How much effort could that be, for containing gas in the same area that you
are sitting? I would call that a no-brainer.
--
Jim in NC

[clare at snyder.on.ca]

On Sun, 4 Mar 2007 21:19:37 -0500, "Morgans"
> wrote:

>
>"Capt. Geoffrey Thorpe" > wrote
>>
>> I watched two people burn to death in front of the airshow crowd at
>> Oshkosh 20 some years ago when this type of fuel cap popped off after a
>> T-18 hit the ground inverted. The occupants survived the impact and were
>> pleading for help on the radio. Unfortunatly, the aircraft was sitting in
>> a big puddle of burning fuel and no one could get to them. By the time the
>> fire trucks arrived, they were dead.
>>
>> This style of fuel cap falls into my "not recommended" catagory.
>
>Wow, rough way to go. I would have to agree with you.
>
>I would think that a fitting threaded into less than 1/8" of plastic would
>fall into the same type of danger category. They could blow out, or be
>pushed out, with a minimum of effort, not to mention the current problem of
>leakage.
>
>An inspection and access hole could be made so easily, and a plate of
>aluminum and gasket with a backing plate (or ring) to screw into could be
>done so easily, I would think that would be the first choice. Then, a
>fitting with a true nut and O-ring could be used on all of the fittings,
>with security, and no problems with leaks.
>
>How much effort could that be, for containing gas in the same area that you
>are sitting? I would call that a no-brainer.


A no-brainer is a "dip tube" fuel outlet, where the fitting goes in
the TOP of the tank. Only caveat is you need a fuel pump.

--
Posted via a free Usenet account from http://www.teranews.com

[[email protected]]

On Mar 1, 1:55 am, "Rob Turk" > wrote:
> I'm looking for a sealant or kit to seal brass NPT inserts into a
> polyethylene tank. This is a Kitfox header tank that has developed a leak at
> one of the inserts. I'm probably going to use Mogas that has ethanol
> additives. Any hints, tips, thoughts?
>
> Thanks,
> Rob

Hey Rob,

Before you mess up a perfectly good tank....

Just back that brass insert out. It's a pipe thread. Clean up the
mess as best you can.

I've have very good service using the thread sealant that Aircraft
Spruce sells called EZ Turn. I sealed every joint in the fuel system
that used that old white sealant. Some of them were leaking esp. at
the fiberglass wing tanks.

http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php

Also try surfing the matronics Kitfox list.

Cheers,

Mark Napier

N246DR KFIII 582

[Rob Turk]

> wrote in message
oups.com...
> Hey Rob,
>
> Before you mess up a perfectly good tank....
>
> Just back that brass insert out. It's a pipe thread. Clean up the
> mess as best you can.
>
> I've have very good service using the thread sealant that Aircraft
> Spruce sells called EZ Turn. I sealed every joint in the fuel system
> that used that old white sealant. Some of them were leaking esp. at
> the fiberglass wing tanks.
>
> http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php
>
> Also try surfing the matronics Kitfox list.
>
> Cheers,
>
> Mark Napier

Hi Mark, thanks for the tip. Certainly worth looking into..
Thanks!
Rob

[Tri-Pacer]

I just looked at one of these jewels yesterday and I am impressed. Is anyone
using one? How do you like it. I'd really like to hear pro's and cons. I'm
presently using a King Skymap IIIC and could probably sell if for what a
Lowrance 2000C would cost.



Thanks



Paul Anton

N1431A

KPLU

[Juan Jimenez[_1_]]

I wrote a review of this unit back in 2005. Three parts.

http://www.aero-news.net/news/featurestories.cfm?ContentBlockID=866cc774-b4fc-4c40-afcc-a409a6af83f4&Dynamic=1
http://www.aero-news.net/news/featurestories.cfm?ContentBlockID=7a191058-4597-4ddb-94ef-3f5ec92f0c0e&Dynamic=1
http://www.aero-news.net/news/featurestories.cfm?ContentBlockID=E5F7E835-AAE3-4E04-AF75-7B842111537A&Dynamic=1

I have not updated the review nor been informed of any changes to the
product.

Juan


"Tri-Pacer" > wrote in message
. ..
>I just looked at one of these jewels yesterday and I am impressed. Is
>anyone using one? How do you like it. I'd really like to hear pro's and
>cons. I'm presently using a King Skymap IIIC and could probably sell if for
>what a Lowrance 2000C would cost.
>
>
>
> Thanks
>
>
>
> Paul Anton
>
> N1431A
>
> KPLU
>
>



--
Posted via a free Usenet account from http://www.teranews.com

[Frank Beagle]

Paul,

I've had the 2000c since it originaly was introduced. With the latest
upgrade all the pickey things that Juan alluded to have been fixed and
then some. If you read the manual, and UNDERSTAND what it's telling
you, you will find this unit has features that competitors costing $$$$
$$$ more don't have.

I'm in love with the big color screen, the optional screens are great
tooPlus you can configure the info shown on each page to suit
yourself.

Buy it, you won't be sorry...

Frank "WOOF" Beagle
Challenger Dealer CHII N797FB
http://www.geocities.com/frankbeagle
http://frankbeagle.blogspot.com
ph# 708-269-8057





Tri-Pacer wrote:
> I just looked at one of these jewels yesterday and I am impressed. Is anyone
> using one? How do you like it. I'd really like to hear pro's and cons. I'm
> presently using a King Skymap IIIC and could probably sell if for what a
> Lowrance 2000C would cost.
>
>
>
> Thanks
>
>
>
> Paul Anton
>
> N1431A
>
> KPLU

[Juan Jimenez[_1_]]

"Frank Beagle" > wrote in message
oups.com...
> Paul,
>
> I've had the 2000c since it originaly was introduced. With the latest
> upgrade all the pickey things that Juan alluded to have been fixed and
> then some.

I'm glad to hear that. Some of the issues I pointed out could be called
"pickey" but my background is in IT, and quality control is important to me.



--
Posted via a free Usenet account from http://www.teranews.com